Sodium Hexametaphosphate
Sodium hexametaphosphate, also known as Graham’s salt or SHMP, is a white powder or colorless transparent glassy solid with the chemical formula (NaPO3)6 and molecular weight of 611.77 g/mol. It is highly hygroscopic, readily soluble in water forming a clear solution, but insoluble in organic solvents. With a density of about 2.484 g/cm³, it has a melting point of 616°C where it decomposes. It acts as a sequestrant by forming complexes with metal ions like calcium and magnesium, and its pH in 1% solution is 5.8-7.3. Produced by heating sodium metaphosphate, it is a mixture of polymeric metaphosphates.
Sodium Hexametaphosphate
Widely used in water treatment as a scale inhibitor in EDI, RO, and NF systems. In the food industry, it improves water retention in meats, prevents oxidation, and enhances texture in soy products. Also applied in detergents, ceramics as a dispersant, paints, and metal finishing.
Generally safe but can irritate eyes, skin, and respiratory tract. Avoid strong acids or oxidizers to prevent heat or decomposition. Use PPE and ventilate areas. Not hazardous for transport; store dry to avoid moisture.
Typically in 25kg polypropylene bags with PE liners or 50kg fiber drums. Store in cool, dry, ventilated spaces away from incompatibles.
